SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5556f4fb1b9122dd9bba4b946b5f20bbe3f9810f2e8fd2527ba58f5d5d83043f' 
  AND token = '27Sps6WW2UrIzC+oNfLxYz2h8YfycQGY7VXl5gQclQs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}